Design of Catalytic Membrane Reactors for Biomass Hydrolysis and Separation

Pi：Qian，向红，S.Ranil Wickramasinghe研究所：阿肯色大学建议编号：1264896标题：生物质催化膜反应器的设计本项目的总体目标是开发一种用于生物质转化的催化膜反应器，以低成本获得高产量的糖。大多数生产生物燃料的液相加工技术都是从单体糖(葡萄糖、果糖、木糖等)开始的。来自生物质的分馏。目前的模式使用腐蚀性的稀硫酸进行预处理，以水解半纤维素。相对昂贵的酶被用来分解纤维素。目前的技术使产糖量低，成本高。PI将通过设计硫酸和酶替代催化剂来克服这些问题，这些催化剂的转化率比类似的天然酶高，生产成本也低得多。PI旨在开发可重复使用的环保催化剂，用于在水、混合水和离子液体(IL)溶剂中一步转化半纤维素和纤维素。通过立即分离水解的单体糖，从而最大限度地减少降解，将提高产糖量。选择合适的膜及其孔径将允许单体糖流的渗透和IL的保留以供重复使用。该项目本质上是多学科的，包括通过表面修饰合成催化剂、产品分离和计算化学。生物质的低成本转化将通过以下方法实现：o将组合方法应用于计算设计纤维素和半纤维素水解的酶替代催化剂到单体糖中。o将计算设计的纳米结构从多孔无机膜表面接枝，以构建同时用于水解和糖分离的催化膜反应器。智力优势：将设计和合成由两个相邻的聚合物纳米结构组成的固体酸催化剂。基于聚苯乙烯磺酸(PSSA)的纳米结构将被固定在无机膜表面，并用于催化生物质的水解。邻近的聚合物离子液体(PIL)纳米结构有助于溶解纤维素，提高催化活性。溶解的单体糖将通过膜的孔从反应介质中提取出来。PSSA聚合物纳米结构的酸性和结合亲和力可以通过环取代和/或共聚来调节。这项研究的完成将导致一种催化膜反应器，用于同时水解纤维素和半纤维素，从而最大限度地提高产糖量。材料科学的进展将包括从膜表面嫁接复杂的定制纳米结构的新的表面改性方法。广泛的影响：从纤维素生物质中开发生物燃料作为化石燃料的替代品可能会产生重要的社会影响：生物燃料是可再生和可持续的能源；使用生物燃料可以帮助将温室气体对环境的排放降至最低。这项研究是多学科的，为研究生和本科生提供了教育和培训机会。与德国杜伊斯堡-埃森大学的国际合作将为参与该项目的学生提供国际经验。向代表人数不足的少数群体推广科学和工程的外联活动是这些活动的组成部分。研究和教育成果将在同行评议的期刊上广泛传播。这项工作将导致培训一支新的熟练劳动力队伍，以应对从化石燃料主导的炼油业向未来的生物炼油业转型的挑战。

PI: Qian, Xianghong and S. Ranil WickramasingheInstitution: University of ArkansasProposal Number: 1264896Title: Design of Catalytic Membrane Reactor for Biomass Hydrolysis and SeparationThe overall objective of this project is to develop a catalytic membrane reactor for biomass conversion that results in high yields of sugar at low cost. Most liquid phase processing technologies for production of biofuels start with monomer sugars (glucose, fructose, xylose, etc.) from biomass fractionation. The current paradigm uses corrosive, dilute sulfuric acid for pretreatment to hydrolyze hemicelluloses. Relatively expensive enzymes are used to break down cellulose. Current technology gives low sugar yields at high cost. The PIs will overcome these problems by designing sulfuric acid and enzyme replacement catalysts that operate at a higher conversion rate than the analogous natural enzymes and that cost far less to produce. The PIs aim to develop reusable, environmentally friendly catalysts for conversion of hemicelluloses and cellulose in one step in an aqueous, mixed water and ionic liquid (IL) solvent. Sugar yields will be improved by immediate separation of hydrolyzed monomer sugars thus minimizing degradation. The appropriate choice of the membrane and its pore size will allow permeation of an aqueous monomeric sugar stream and retention of the IL for reuse.This project is multidisciplinary in nature, encompassing catalyst synthesis via surface modification, product separation and computational chemistry. Low cost conversion of biomass to produce high yields of sugar will be achieved via the following approaches:o Application of combinatorial methods to the computational design of enzyme replacement catalysts for cellulose and hemicellulose hydrolysis to monomer sugars.o Grafting computationally designed nanostructures from porous inorganic membrane surfaces in order to build a catalytic membrane reactor for simultaneous hydrolysis and sugar separation.Intellectual Merit: Solid-acid catalysts made of two neighboring polymeric nanostructures will be designed and synthesized. A polystyrene sulfonic acid (PSSA)-based nanostructure will be immobilized on inorganic membrane surfaces and used to catalyze biomass hydrolysis. A neighboring polymeric ionic liquid (PIL) nanostructure will help solubilize cellulose and enhance the catalytic activity. The solubilized monomer sugars will then be extracted from the reaction media through the pores of the membrane. The acidity and binding affinity of a PSSA polymer nanostructure can be tuned by ring substitution and/or copolymerization. Completion of the research will result in a catalytic membrane reactor for simultaneous hydrolysis of cellulose and hemicellulose that maximizes sugar yields. Advances in materials science will include new surface modification methods for grafting complex customized nanostructures from membrane surfaces.Broader Impacts: Development of biofuels from cellulosic biomass as a replacement for fossil fuels could have important societal impacts: biofuels are renewable and sustainable energy sources; using biofuels can help minimize emissions of greenhouse gases to the environment. The research is multidisciplinary, leading to education and training opportunities for both graduate and undergraduate students. International collaboration with University of Duisburg-Essen in Germany will provide international experiences for the students working on this project. Outreach activities that promote science and engineering to underrepresented minorities are an integral part of the these activities. The research and educational results will be disseminated widely in peer-reviewed journals. This work will result in the training of a new skilled work force in an to meet the challenges in moving from a fossil fuel dominated refinery industry to a future biorefinery industry.